Test tool for power supply chip

Abstract

The embodiment of the utility model relates to the technical field of power supply chip testing, and discloses a power supply chip testing tool which comprises a testing seat, a printed circuit board provided with a testing circuit and a shell, the testing seat is arranged in the middle of the front surface of the shell, the printed circuit board is arranged in the shell, a plurality of circular holes are formed in the shell, and the testing circuit is arranged in the circular holes. A power-up port, an output port and a test port are formed at the exposed position; the test seat is used for loading a power supply chip, and the power supply chip is communicated with a test circuit designed in the printed circuit board after being loaded on the test seat; the power-up port is used for accessing input voltage provided by a direct-current power supply through the power supply clamp; the output port is connected with an electronic load through a connecting line; the test port is connected with the oscilloscope through the oscilloscope test probe or is connected with the voltmeter through the voltmeter test probe, so that the power supply chip is tested, the index abnormity phenomenon caused by machine operation is avoided, the product quality is improved, and the production speed and the production efficiency are improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of power chip testing, and in particular to a testing tool for a power chip. Background Art

[0002] In the electronics industry, the domestic power chip LYM4633IY, as an alternative model to the foreign-produced chip LTM4633IY#PBF, has been widely and commonly used under the general trend of localization.

[0003] However, due to objective reasons such as equipment and test sockets, the power chip LYM4633IY lacks reliable testing methods, and its related tests need to be implemented through on-machine verification. The real-time and flexibility of the test are insufficient, and it is impossible to perform index tests or functional tests such as maximum load capacity. If problems with the power chip LYM4633IY are found on the production line, it will seriously affect the production schedule. Utility Model Content

[0004] The purpose of the embodiment of the present application is to provide a test tool for a power chip, which can test the power chip LYM4633IY before the product is used, eliminate unqualified products in the first stage, avoid abnormal indicators after being put into the machine, improve product quality and reliability, and improve production speed and efficiency.

[0005] In order to achieve the above-mentioned purpose, an embodiment of the present application provides a test fixture for a power chip, including a test socket, a printed circuit board designed with a test circuit, and a shell, wherein the test socket is arranged in the middle position of the front surface of the shell, the printed circuit board is arranged inside the shell, and a plurality of circular holes are opened on the shell to form a power-on port, three output ports and three test ports of the test fixture at the position where the printed circuit board is exposed, and the test ports correspond to the output ports one by one; the test socket is used to load a power chip, and the power chip is connected with the test circuit designed in the printed circuit board after being loaded on the test socket; the power-on port is used to connect to the input voltage provided by a DC power supply through a power supply fixture; the output port is connected to an electronic load through a connecting line, and is used to test the maximum load capacity of the power chip; the test port is connected to an oscilloscope through an oscilloscope test probe or is connected to a voltmeter through a voltmeter test probe, the oscilloscope is used to obtain the ripple of the output voltage of the output port corresponding to the test port, and the voltmeter is used to obtain the voltage value of the output voltage of the output port corresponding to the test port.

[0006] The embodiment of the present application provides a test fixture for a power chip, the test fixture is composed of a test socket, a printed circuit board designed with a test circuit, and a shell, the test socket is arranged in the middle of the front surface of the shell, the printed circuit board is arranged inside the shell, and a number of round holes are opened on the shell to form a power-on port, three output ports, and three test ports of the test fixture at the position where the printed circuit board is exposed, and the test ports correspond to the output ports one by one. The test socket is responsible for loading the power chip; the power-on port is responsible for connecting the input voltage; the output port is responsible for connecting the electronic load to test the maximum load capacity of the power chip; the test port is responsible for connecting to an oscilloscope or a voltmeter to measure the output voltage ripple and the output voltage value of the output port corresponding to the test port. When testing, the power chip is loaded on the test socket, the input voltage is provided to the power chip through the DC power supply and the power supply fixture, the output port is connected to the electronic load through the connecting wire, the maximum load capacity of the power chip is tested, the test port is connected to the oscilloscope through the oscilloscope test probe, the ripple of the output voltage of the corresponding output port is obtained, and the test port is connected to the voltmeter through the voltmeter test probe to obtain the voltage value of the output voltage of the corresponding output port. Such a test fixture can test the power chip LYM4633IY before the product is used, eliminate unqualified products in the first link, avoid abnormal indicators after being put into the machine, improve the quality and reliability of the product, and improve the production speed and efficiency.

[0007] In some optional embodiments, the test circuit is provided with an input voltage decoupling capacitor near the corresponding position of the power-on port, and the input voltage decoupling capacitor is composed of four ceramic capacitors with a nominal capacity of 22μF and a nominal withstand voltage of 25V connected in parallel; the test circuit is provided with an output voltage decoupling capacitor near the corresponding position of the output port, and the output voltage decoupling capacitor is composed of two ceramic capacitors with a nominal capacity of 100μF and a nominal withstand voltage of 10V connected in parallel; the input voltage decoupling capacitor and each output voltage decoupling capacitor are both provided on the back of the printed circuit board. Providing the input voltage decoupling capacitor and each output voltage decoupling capacitor on the back of the printed circuit board can save space and ensure that the decoupling capacitors are placed according to the principle of proximity.

[0008] In some optional embodiments, the three output ports are respectively a first output port, a second output port and a third output port, the first output port corresponds to the first output pin of the test circuit, the second output port corresponds to the second output pin of the test circuit, and the third output port corresponds to the third output pin of the test circuit; a first feedback resistor is provided between the inverting input pin of the first error amplifier of the test circuit and the ground pin, a second feedback resistor is provided between the inverting input pin of the second error amplifier of the test circuit and the ground pin, and a third feedback resistor is provided between the inverting input pin of the third error amplifier of the test circuit and the ground pin. The setting of the feedback resistor can adjust the output voltages of the three output ports so that the output voltages of the three output ports meet the test requirements.

[0009] In some optional embodiments, the voltage value of the output voltage of the first output port is 1.5V, the voltage value of the output voltage of the second output port is 1.2V, the voltage value of the output voltage of the third output port is 3.3V, and the voltage value of the input voltage connected to the power port is 12V; the resistance value of the first feedback resistor is 69.8kΩ, the resistance value of the second feedback resistor is 121kΩ, and the resistance value of the third feedback resistor is 19.1kΩ.

[0010] In some optional embodiments, the connection between the output port and the electronic load is disconnected, that is, the output port is set to no-load, the voltage value of the input voltage connected to the power port is adjusted, the voltage value of the output voltage of the output port and the change value of the output voltage are read through the voltmeter, and the voltage regulation rate of the power chip is determined based on the ratio of the change value of the output voltage to the voltage value of the output voltage. The voltage regulation rate is one of the important indicators for considering voltage stability. The test fixture proposed in this application can quickly and accurately measure the voltage regulation rate, thereby quickly and efficiently completing the test of the voltage stability of the power chip.

[0011] In some optional embodiments, the voltage value of the input voltage connected to the power port is fixed, the load value provided by the electronic load is adjusted, the voltage value of the output voltage of the output port and the change value of the output voltage are read through the voltmeter, and the current regulation rate of the power chip is determined based on the ratio of the change value of the output voltage to the voltage value of the output voltage. The current regulation rate is one of the important indicators for considering voltage stability. The test fixture proposed in this application can quickly and accurately measure the current regulation rate, thereby quickly and efficiently completing the test of the voltage stability of the power chip.

[0012] In some optional embodiments, a direction indicator mark is provided on the front surface of the housing, and the direction indicator mark is used to indicate the installation direction of the power chip. The setting of the direction indicator mark can ensure that the technician correctly loads the power chip on the test socket, avoids damage to the test tooling and the power chip due to incorrect loading, and can further improve the test speed and test efficiency of the power chip.

[0013] In some optional embodiments, the printed circuit board is made of FR-4 four-layer board, and the size of the printed circuit board is 120mm×105mm. Such a printed circuit board can ensure smooth signal routing, the signal line is as short as possible, ensure the maximum current passing through the same line width, and ensure good contact between the power chip and the printed circuit board (test circuit). BRIEF DESCRIPTION OF THE DRAWINGS

[0014] One or more embodiments are exemplarily described by the pictures in the corresponding drawings, and these exemplary descriptions do not constitute limitations on the embodiments.

[0015] Figure 1 It is a structural schematic diagram of a test fixture for a power chip provided by an embodiment of the present application;

[0016] Figure 2 It is a schematic diagram of a test tool for a power chip performing a test task provided by an embodiment of the present application;

[0017] Figure 3 It is a schematic diagram of a partial test circuit on a power port side provided by an embodiment of the present application;

[0018] Figure 4 It is a schematic diagram of a partial test circuit on an output port side provided by an embodiment of the present application. DETAILED DESCRIPTION

[0019] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the present application, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present application can also be implemented. The division of the following embodiments is for the convenience of description, and the specific implementation of the present application should not be construed as any limitation, and the various embodiments can be combined and referenced with each other under the premise of no contradiction.

[0020] An embodiment of the present application proposes a test tool for a power chip. The implementation details of the test tool for a power chip proposed in this embodiment are specifically described below. The following content is only the implementation details provided for the convenience of understanding and is not necessary for implementing this solution.

[0021] The specific structure of a power chip test fixture proposed in this embodiment can be as follows: Figure 1 As shown, the connection relationship between each device when executing the test task can be as follows Figure 2 As shown, the test fixture 10 includes a test socket 11, a printed circuit board 12 designed with a test circuit, and a shell 13. The test socket 11 is arranged in the middle position of the front surface of the shell 13, and the printed circuit board 12 is arranged inside the shell 13. The shell 13 is provided with a plurality of circular holes, which are used to form a power-on port 14, three output ports (i.e., a first output port 151, a second output port 152, and a third output port 153) and three test ports (i.e., a first test port 161, a second test port 162, and a third test port 163) of the test fixture 10 at a position where the printed circuit board 12 is exposed. The test ports correspond one-to-one to the output ports, the first output port 151 corresponds to the first test port 161, the second output port 152 corresponds to the second test port 162, and the third output port 153 corresponds to the third test port 163.

[0022] The test socket 11 is used to load the power chip, which is connected to the test circuit designed in the printed circuit board 12 after being loaded on the test socket 11; the power port 14 is used to access the input voltage provided by the DC power supply 20 through the power supply fixture; the output port is connected to the electronic load 30 through a connecting line (the first output port 151 is connected to channel 1 of the electronic load 30, the second output port 152 is connected to channel 2 of the electronic load 30, and the third output port 153 is connected to channel 3 of the electronic load 30), which is used to test the maximum load capacity of the power chip; the test port is connected to the oscilloscope 40 through an oscilloscope test probe or is connected to the voltmeter 50 through a voltmeter test probe, the oscilloscope 40 is used to obtain the ripple of the output voltage of the output port corresponding to the test port, and the voltmeter 50 is used to obtain the voltage value of the output voltage of the output port corresponding to the test port.

[0023] In one example, the power chip LYM4633IY is packaged in the form of a BGA package (Ball Grid Array Package, integrated circuit package). Considering its large output current, when testing the power chip, the probe crimping method is used to complete the test, and the probe is kept as short as possible to shorten the transmission path, thereby reducing voltage and current losses.

[0024] In one example, the supply voltage of the power chip LYM4633IY ranges from 4.7V to 16V, the output voltage of the first and second output ports ranges from 0.8V to 1.8V, and the output voltage of the third output port ranges from 0.8V to 5.5V. Therefore, under the premise of meeting the design requirements, the design selection of input voltage and output voltage should follow two points. First, the voltage commonly used in engineering should be selected, and second, the input current should be as small as possible to reduce the heat loss of the device. Based on these two principles, the input voltage value of the power port is selected to be 12V, the output voltage value of the first output port is set to 1.5V, the output voltage value of the second output port is set to 1.2V, and the output voltage value of the third output port is set to 3.3V.

[0025] In one example, the test circuit is provided with an input voltage decoupling capacitor near the corresponding position of the power-on port. The input voltage decoupling capacitor is composed of four ceramic capacitors with a nominal capacity of 22μF and a nominal withstand voltage of 25V connected in parallel. The test circuit is provided with an output voltage decoupling capacitor near the corresponding position of the output port. The output voltage decoupling capacitor is composed of two ceramic capacitors with a nominal capacity of 100μF and a nominal withstand voltage of 10V connected in parallel. The input voltage decoupling capacitor and each output voltage decoupling capacitor are all arranged on the back of the printed circuit board, which can save space and ensure that the decoupling capacitors are placed according to the principle of proximity. Part of the test circuit on the power-on port side can be as follows Figure 3 As shown, part of the test circuit on the output side can be Figure 4 shown.

[0026] In an example, Figure 1 , Figure 4 As shown, the three output ports are the first output port 151, the second output port 152 and the third output port 153. The first output port 151 corresponds to the first output pin VOUT1 of the test circuit, the second output port 152 corresponds to the second output pin VOUT2 of the test circuit, and the third output port 153 corresponds to the third output pin VOUT3 of the test circuit. A first feedback resistor R is provided between the inverting input pin VFB1 of the first error amplifier of the test circuit and the ground pin GND. FB1 A second feedback resistor R is provided between the inverting input pin VFB2 of the second error amplifier of the test circuit and the ground pin GND. FB2 A third feedback resistor R is provided between the inverting input pin VFB3 of the third error amplifier of the test circuit and the ground pin GND. FB3 The setting of the feedback resistor can adjust the output voltage of the three output ports so that the output voltage of the three output ports meets the test requirements.

[0027] Taking VFB1 as an example, considering that the PWM (Pulse Width Modulation) controller has an internal reference voltage (0.8V±1%), a 60.4kΩ resistor is connected between VOUT1 and VFB1, so it is necessary to set an R between VFB1 and GND. FB1 To control the output voltage of the first output port, the control formula can be expressed as:

[0028]

[0029] In the formula, R FB1 represents the organization of the first feedback resistor, V OUT1 Indicates the voltage value of the output voltage of the first output port.

[0030] In one example, since the voltage value of the input voltage connected to the selected power port is 12V, the voltage value of the output voltage of the first output port is set to 1.5V, the voltage value of the output voltage of the second output port is 1.2V, and the voltage value of the output voltage of the third output port is 3.3V, so the resistance value of the first feedback resistor needs to be set to 69.8kΩ, the resistance value of the second feedback resistor needs to be set to 121kΩ, and the resistance value of the third feedback resistor needs to be set to 19.1kΩ. In addition, in order to ensure voltage accuracy, the first feedback resistor, the second feedback resistor, and the third feedback resistor are all selected to have an accuracy of 1%.

[0031] In an example, when the electronic load is loaded to the maximum load (i.e., 10A), considering that the test socket probe has a resistance of about 100μΩ, certain losses will be generated in the circuit, which will affect the voltage test results. Taking the first output pin as an example, there are actually multiple first output pins. In the circuit design, an independent first output pin is selected, which is not connected to other first output pins, as the test port to ensure the accuracy of the voltage test.

[0032] In one example, the printed circuit board is made of FR-4 four-layer board, the maximum output load is designed to be 10A, the middle layer is 2 ounces of copper, and the size of the printed circuit board is 120mm×105mm. Such a printed circuit board can ensure smooth signal routing, the signal line is as short as possible, ensure the maximum current passing through the same line width, and ensure good contact between the power chip and the printed circuit board (test circuit).

[0033] In an example, Figure 1As shown, a direction indicator mark is provided on the front surface of the housing 13, and the direction indicator mark is used to indicate the installation direction of the power chip. The setting of the direction indicator mark can ensure that the technician correctly loads the power chip on the test socket, avoids damage to the test tooling and the power chip due to incorrect loading, and can further improve the test speed and test efficiency of the power chip.

[0034] In one example, when conducting a test, the LYM4633IY power chip to be tested is loaded into the test socket. After ensuring good contact of the device, the power supply fixture is used to connect the power-on port of the test fixture to the output of the DC power supply. The first output port, the second output port, and the third output port on the test factory are connected to channels 1, 2, and 3 of the electronic load through connecting wires, respectively. The input voltage provided by the DC power supply is set to 12V, and the electronic load provided by the three channels of the electronic load is set to 10A. The DC power supply switch is turned on. The test fixture and the LYM4633IY power chip are now powered on. The output of the electronic load is turned on, and the three-way output load of the LYM4633IY power chip reaches 10A. At this time, the maximum load capacity of the LYM4633IY power chip is verified.

[0035] In one example, the oscilloscope is connected to three test ports on the test fixture through an oscilloscope test probe, the three test ports are measured, and the test results of the oscilloscope are read to obtain the output voltage ripple of the output port corresponding to each test port.

[0036] In one example, the voltmeter is connected to three test ports on the test fixture through a voltmeter test probe, the three test ports are measured, and the test results of the voltmeter are read to obtain the voltage value of the output voltage of the output port corresponding to each test port.

[0037] In one example, disconnect the output port from the electronic load, that is, set the output port to no-load, adjust the voltage value of the input voltage connected to the power port (adjustment range is 4.7V to 16V), read the output voltage value and the output voltage change value of the output port through a voltmeter, and determine the voltage regulation rate of the power chip based on the ratio of the output voltage change value to the output voltage value. Voltage regulation rate is one of the important indicators for considering voltage stability. The test fixture can quickly and accurately measure the voltage regulation rate, thereby quickly and efficiently completing the test of voltage stability of the power chip.

[0038] In one example, the voltage value of the input voltage connected to the power port is fixed (12V), the load value provided by the electronic load is adjusted (the adjustment range is 0A to 12A), the voltage value of the output voltage of the output port and the change value of the output voltage are read through the voltmeter, and the current regulation rate of the power chip is determined based on the ratio of the change value of the output voltage to the voltage value of the output voltage. The current regulation rate is one of the important indicators for considering voltage stability. The test fixture can quickly and accurately measure the current regulation rate, thereby quickly and efficiently completing the test of the voltage stability of the power chip.

[0039] In this embodiment, the test fixture is composed of a test seat, a printed circuit board designed with a test circuit, and a shell. The test seat is arranged in the middle of the front surface of the shell, and the printed circuit board is arranged inside the shell. The shell is provided with a number of round holes to form a power-on port, three output ports, and three test ports of the test fixture at the position where the printed circuit board is exposed, and the test ports correspond to the output ports one by one. The test seat is responsible for loading the power chip; the power port is responsible for connecting the input voltage; the output port is responsible for connecting the electronic load to test the maximum load capacity of the power chip; the test port is responsible for connecting with an oscilloscope or a voltmeter to measure the ripple of the output voltage and the voltage value of the output voltage of the output port corresponding to the test port. When testing, the power chip is loaded on the test seat, the input voltage is provided to the power chip through a DC power supply and a power supply fixture, the output port is connected to the electronic load through a connecting line, the maximum load capacity of the power chip is tested, the test port is connected to the oscilloscope through an oscilloscope test probe, the ripple of the output voltage of the corresponding output port is obtained, and the test port is connected to the voltmeter through a voltmeter test probe to obtain the voltage value of the output voltage of the corresponding output port. Such testing tooling can test the power chip LYM4633IY before the product is used, eliminate unqualified products in the first stage, avoid abnormal indicators after being put into the machine, improve product quality and reliability, and increase production speed and efficiency.

[0040] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present application, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present application.

Claims

1. A test tool for a power chip, characterized in that: The test fixture comprises a test socket, a printed circuit board with a test circuit, and a housing, wherein the test socket is arranged in the middle of the front surface of the housing, the printed circuit board is arranged inside the housing, and a plurality of round holes are opened on the housing to form a power-on port, three output ports, and three test ports of the test fixture at the position where the printed circuit board is exposed, and the test ports correspond to the output ports one by one; The test socket is used to load a power chip, and after the power chip is loaded on the test socket, it is connected with the test circuit designed in the printed circuit board; The power supply port is used to connect to the input voltage provided by the DC power supply through the power supply fixture; The output port is connected to an electronic load via a connecting line, so as to test the maximum load capacity of the power chip; The test port is connected to an oscilloscope via an oscilloscope test probe or to a voltmeter via a voltmeter test probe. The oscilloscope is used to obtain the ripple of the output voltage of the output port corresponding to the test port, and the voltmeter is used to obtain the voltage value of the output voltage of the output port corresponding to the test port.

2. A power chip testing tool according to claim 1, characterized in that: The test circuit is provided with an input voltage decoupling capacitor near the corresponding position of the power-on port, and the input voltage decoupling capacitor is composed of four ceramic capacitors with a nominal capacity of 22 μF and a nominal withstand voltage of 25 V connected in parallel; The test circuit is provided with an output voltage decoupling capacitor near the corresponding position of the output port, and the output voltage decoupling capacitor is composed of two ceramic capacitors with a nominal capacitance value of 100 μF and a nominal withstand voltage value of 10V connected in parallel; The input voltage decoupling capacitor and each of the output voltage decoupling capacitors are arranged on the back side of the printed circuit board.

3. A power chip testing tool according to claim 2, characterized in that: The three output ports are respectively a first output port, a second output port and a third output port, the first output port corresponds to a first output pin of the test circuit, the second output port corresponds to a second output pin of the test circuit, and the third output port corresponds to a third output pin of the test circuit; A first feedback resistor is arranged between the inverting input pin of the first error amplifier of the test circuit and the ground pin, a second feedback resistor is arranged between the inverting input pin of the second error amplifier of the test circuit and the ground pin, and a third feedback resistor is arranged between the inverting input pin of the third error amplifier of the test circuit and the ground pin.

4. A power chip testing tool according to claim 3, characterized in that: The output voltage of the first output port is 1.5V, the output voltage of the second output port is 1.2V, the output voltage of the third output port is 3.3V, and the input voltage of the power port is 12V. The resistance value of the first feedback resistor is 69.8 kΩ, the resistance value of the second feedback resistor is 121 kΩ, and the resistance value of the third feedback resistor is 19.1 kΩ.

5. The power chip testing tool according to claim 1, characterized in that: Disconnect the output port from the electronic load, that is, set the output port to be unloaded, adjust the voltage value of the input voltage connected to the power port, read the voltage value of the output voltage of the output port and the change value of the output voltage through the voltmeter, and determine the voltage regulation rate of the power chip based on the ratio of the change value of the output voltage to the voltage value of the output voltage.

6. The test fixture for a power chip according to claim 1, characterized in that: The voltage value of the input voltage connected to the power port is fixed, the load value provided by the electronic load is adjusted, the voltage value of the output voltage of the output port and the change value of the output voltage are read through the voltmeter, and the current regulation rate of the power chip is determined based on the ratio of the change value of the output voltage to the voltage value of the output voltage.

7. A power chip testing tool according to any one of claims 1 to 6, characterized in that: A direction indication mark is arranged on the front surface of the shell, and the direction indication mark is used to indicate the installation direction of the power chip.

8. A power chip testing tool according to any one of claims 1 to 6, characterized in that: The printed circuit board is made of FR-4 four-layer board, and the size of the printed circuit board is 120mm×105mm.

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